Field of the Invention
The present invention relates a developing apparatus that develops an electrostatic latent image formed on a photosensitive drum and is attachable/detachable to/from an apparatus main body of an image forming apparatus, and a process cartridge that forms a developer image on a photosensitive drum and is attachable/detachable to/from an apparatus main body of an image forming apparatus. In addition, the present invention relates to an image forming apparatus that forms an image on a recording medium by using an electrophotographic technology.
Description of the Related Art
Conventionally, image forming apparatuses that form images on recording media such as sheets using an electrophotographic technology have been known. As such, printers (such as laser beam printers and LED printers), copiers, facsimile machines, word processors, multifunction peripherals (multifunction printers), or the like have been, for example, known.
In such an image forming apparatus, a photosensitive drum is uniformly charged by a charging roller. Further, the charged photosensitive drum is selectively exposed to form an electrostatic image on the photosensitive drum. The electrostatic image having been formed on the photosensitive drum is developed as a toner image by a developing apparatus. Further, the toner image having been formed on the photosensitive drum is transferred onto a recording medium such as a recording paper and a plastic sheet. After that, the toner image having been transferred onto a recording material is heated and pressed to be fixed onto the recording medium. In the manner described above, an image is formed on the recording medium.
In such an image forming apparatus, a photosensitive drum, a charging roller, a developing apparatus, and the like are integrated with each other as a cartridge to facilitate the maintenance of parts inside the image forming apparatus. In addition, as a process cartridge, a configuration such as a cleaning cartridge having a photosensitive drum, a developing cartridge serving as a developing apparatus having developing means, a toner cartridge that supplies a developer has been known.
Here, in a technology disclosed in Japanese Patent Application Laid-open No. 2013-182036, a developing cartridge is allowed to be attached/detached to/from the apparatus main body of an image forming apparatus. The developing cartridge has a first frame body that rotatably supports a developing roller and a second frame body that rotatably supports both ends of the first frame body in the longitudinal direction of the developing roller. Further, in a state in which the developing cartridge has been attached to the image forming apparatus, the second frame body of the developing cartridge is positioned and the first frame body thereof is made to be rotatable. Thus, the developing roller is allowed to come in contact with and separate from a photosensitive drum.
However, in the technology disclosed in Japanese Patent Application Laid-open No. 2013-182036, the second frame body that rotatably supports both ends of the first frame body in the longitudinal direction of the developing roller is constituted as one single member. Therefore, in order to provide areas for connecting portions that support both ends of the first frame body with respect to the second frame body, it is necessary to upsize the developing cartridge.
The present invention has an object of preventing the upsize of a developing cartridge serving as a developing apparatus.